Different configurations of the Pixel Detector have been studied to determine which one would be the best wrt pt and impact parameter resolution for tracks. For the tracks we are interested in the pt range compatible with the one of tracks coming from a b-hadron decay (pt~ 3.5 GeV).

We bin our measurement in 4 pt regions: 1 Gev, 2 GeV, 5GeV, 20 GeV. And we consider 3 eta regions: C ( eta< 0.8), I (eta< 1.6), F (eta<2.4).

We use different scenarios:

• TP- Technical Proposal: 4 Layers for the BP with pixel with the same resolution as the Run I in Phase I (13 um x 28 um); sensor: 100 um x 150 um, thickness T=0.3 mm ; innermost layer at 3 cm from the beampipe and the outermost layer 16.1 cm.

• TP with outer layer at 18.8 cm.

• TP but one layer (the 3rd one at radius=10.9 cm) removed.

• TP with better resolution (7um x 15 um) sensors in first layer.

• TP with better resolution (7um x 15 um) sensors in first layer (sensor thickness = 0.225 in the first Layer). [ If the pixel size is decreased 75 um x 100 um, to have the same charge sharing between pixel that we have in the Run I, the thickness should be reduced]

• TP with better resolution (7um x 15 um) sensors in first layer, increasing material of the first layer [ the better resolution pixel has an area that is half compared to the Run I pixel. So in the same detector there will be a double number of pixels and an increase of the material, especially for the read-out].

• TP with better resolution (7um x 15 um) sensors in all 4 layers, (pixel thickness =0.225 in all Layers).

• TP with better resolution (7um x 15 um) sensors in all 4 layers, increasing material in all layers.

• Strawman5 configuration is explained in https://test-lantonel-tklayout.web.cern.ch/test-lantonel-tklayout/Strawman_5/indexpixel.html (with material changes in the tracker, and the reference resolution of 10 um x 15 um).

• Strawman5, with better resolution (7um x 15 um) sensors in 2 innermost ( and extension ) layers, Phase I resolution (13 um x 28 um) sensors in 2 outer layers.

• Strawman5, with better resolution (7um x 15 um) sensors in 2 innermost ( and extension ) layers, Phase I resolution (13 um x 28 um) sensors in 2 outer layers, (pixel thickness =0.225 in 2 layers).

• TP with the number of pixels quadrupled. [Just to test]

The results are reported in the tables: file:///Users/cgalloni/Phase2Upgrade/tklayout/TechnicalProposal2014_Just3Layers/index.html